HDBaseT Extenders and Panasonic 4K TVs

Using an HDBaseT Extender with a Panasonic 4K TV?

The following solution has been tried and proven using a Panasonic TX-55CX740A but should apply to many Panasonic 4K TVs currently out in the market.

What was the problem?

The feedback from engineers and other HDBaseT alliance manufacturers is that the Panasonic screens suffer from a problem that is known as ‘clock stretching‘.

This is the HDMI and EDID information that is carried on the DDC channel. For further explanation please see recent article written by CEPRO

What screens did this effect?

From reports in the field, this appears to be latest 4K Panasonic screens. A list of several screens that this fault has been witnessed are below:

  • TX-40CX700B
  • TX-42AS700
  • TX55CX700
  • TX-65CX700
  • TX-55AX902B (and other sizes in this range)
  • TX-40CX680B
  • TX-55CX740A

Solution

We have installed a Blustream HD11AU at the end of the signal chain and connected from here directly into screen.

Due to HD11 being located as short distance to screen and managing HDMI EDID it appears to solve the clock stretching issue.

This has been tested directly from source and out of Blustream matrix outputs.

We would recommend setting the HD11AU to be a signal end point (mode dip-switch 1 set to 1). The HD11AU can be set to either an end-point in the HDMI signal chain or as pass-through.

In both setups the HDMI signal is stable.

EDID dip-switch settings have been tested @ 4K, 1080P and 1080i so is dependant remaining other display devices in your system.

Blustream recommend 1080P 2ch as default – see the following photo for setup

The HD11AU is a powered product and requires 5V 1amp supply. We would recommend using supplied power adaptor but have also tested running this from the USB 0.5A 5V power supply of the Panasonic screen and HD11AU has been stable.

Further notes:

  • We noted if using long HDMI cables (15m+) that we could not get a signal. All test were done with HDMI cables of less than 5m
  • Within the Panasonic menu system, you need to make the following changes:
    • HDCP MODE SET TO AUTO
    • HDMI MODE CHANGED FROM DEFAULT TO MODE TWO
      (Please note other manufacturers found that their solution required the Panasonic to be set to MODE ONE). You may need to try both settings dependant on your screen and HDBaseT solution.
    • The Panasonic screen does not support multi-channel audio so you will need to set EDID to 2ch or you will miss all of the centre channel audio information.